Clutch issues

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VegasVMax

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Im having a problem with my clutch. When the bike gets warm and I'm at a intersection in gear, the bike wants to creep forward. If im in neutral and shift into first, sometimes it will kill the motor. I flushed the clutch fluid and it helped a little but it's still doing it. The bike has 21,000 miles on it. There is no clutch slippage when accelerating.
 
Check for an air bubble - may be trapped up next to the handlebar master cylinder right where the line hooks to the master. Sometimes when bleeding, any unbled air will accumulate back up there and become trapped and not allow a "full pull" on the plates when the lever is completely pulled in.

Cover all painted surfaces if you crack that banjo bolt loose to check for air there - as we all know how corrosive DOT 3-4 brake fluid can be.

Also, be sure to add enough fluid level to the reservoir so as not to allow any new air to enter down into the lines.
 
When's the last time you changed engine oil? What type do you use?
 
Check for an air bubble - may be trapped up next to the handlebar master cylinder right where the line hooks to the master. Sometimes when bleeding, any unbled air will accumulate back up there and become trapped and not allow a "full pull" on the plates when the lever is completely pulled in.

Cover all painted surfaces if you crack that banjo bolt loose to check for air there - as we all know how corrosive DOT 3-4 brake fluid can be.

Also, be sure to add enough fluid level to the reservoir so as not to allow any new air to enter down into the lines.


I will re bleed the system again this weekend and check for those air bubbles.....Thanx
 
When's the last time you changed engine oil? What type do you use?

I plan on doing a oil change this weekend as it is getting close to 3 months since I've done it. (About 2500 miles). I run 10w40 dino oil . I believe I used Penzoil last change.
 
I noticed better shifting when I changed to Rotella T from Castrol Actevo. Also, when I replaced clutch disks I soaked them in oil over night before installation....seemed to help.
 
Sounds like a disengaging problem. I've seen a notched basket cause issues but that is practically unheard of on the vmax. Typical cause is air in the line, faulty master cylinder or faulty slave cylinder.

Double check that it is bled properly. Make sure nothing is leaking and fluid level is correct. Is master and slave in good condition?
 
I will re bleed the system again this weekend and check for those air bubbles.....Thanx

When you do, stick a flash light right there in the M/C while indexing the lever (carefully cause the fluid will "fountain") and look for "micro" bubbles. I had those in mine for a while after the normal size bubbles stopped coming out.

You can zip tie your lever "in" overnight. This has been known to help.
 
I guess I forgot to mention that when I feel the bike pulling, if I raise the rpm's, the bike stops creeping until the motor returns to normal idle speed.
 
Third on the Rotella, nothing else works as well in these bikes. change it every 1000 miles. It's cheap at wal mart.

Try changing to Rotella and see if it makes any difference. Will someone who knows more than I do explain how engine oil is involved in the hydraulic clutch system. After replacing my clutch I can see that it is but I might be wrong. I think that little ball that goes into the center hole in the clutch main shaft must have engine oil behind it under normal circumstances and the clutch slave cylinder pushes on that oil which pushes on that ball which pushes on the clutch boss and the spring. oil pressure might be low at idle and the clutch might not be properly disengaging.

If this turns out to be the case, install the Morley HD Oiler kit and that low pressure at idle will be history.

Need confirmation on that from someone who's sure. Don't trust me because I completely disassembled my clutch and replaced almost everything. Not Joking or being sarcastic. Everything I just wrote may be wrong.
 
I'm pretty sure the slave cylinder pushes the whole rod, ball, and little hat thing which moves the pressure plate away from the friction disks.
 
Third on the Rotella, nothing else works as well in these bikes. change it every 1000 miles. It's cheap at wal mart.

Try changing to Rotella and see if it makes any difference. Will someone who knows more than I do explain how engine oil is involved in the hydraulic clutch system. After replacing my clutch I can see that it is but I might be wrong. I think that little ball that goes into the center hole in the clutch main shaft must have engine oil behind it under normal circumstances and the clutch slave cylinder pushes on that oil which pushes on that ball which pushes on the clutch boss and the spring. oil pressure might be low at idle and the clutch might not be properly disengaging.

Oil pressure has nothing to do with clutch disengagement.
 
Sounds like a disengaging problem. I've seen a notched basket cause issues but that is practically unheard of on the vmax. Typical cause is air in the line, faulty master cylinder or faulty slave cylinder.

Double check that it is bled properly. Make sure nothing is leaking and fluid level is correct. Is master and slave in good condition?

I think if you follow this advice you will find what you have wrong. Do a search on pushing the fluid up from the slave cyl bleeder as that is I believe the quickest and most-effective method of bleeding your system of excess air. Use a syringe and a short length of 1/4" I.D. clear plastic tubing onto the slave nipple. A 60 ml (60 cc) syringe should make short work of the problem.

As mentioned, if your master is bleeding internally, you will start to have disengagement problems. If you see fluid running down your lever, (it collects at the end of the lever on the underside of that ball) your rear seal is shot and time for a piston kit. :confused2:
 
Oil pressure has nothing to do with clutch disengagement.

I side w/Joe, assuming that you have some! (oil pressure) The clutch is a mechanical disengagement mechanism with oil cooling the clutch plates and letting everything which should, be lubricated for ease of operation.
 
I think if you follow this advice you will find what you have wrong. Do a search on pushing the fluid up from the slave cyl bleeder as that is I believe the quickest and most-effective method of bleeding your system of excess air. Use a syringe and a short length of 1/4" I.D. clear plastic tubing onto the slave nipple. A 60 ml (60 cc) syringe should make short work of the problem.

As mentioned, if your master is bleeding internally, you will start to have disengagement problems. If you see fluid running down your lever, (it collects at the end of the lever on the underside of that ball) your rear seal is shot and time for a piston kit. :confused2:
Nope, I have no leaks.
 
I'll 2nd the motion, or notion, that oil pressure has nothing to do with clutch disengagement. If you are getting a full pull of clutch lever and it's brake fluid contained therein, oil pressure would have no part in whether or not the clutch was still trying to pull the bike forward. When the clutch IS creeping, and you increase RPM's, you are causing the discs/pads to slide more easily even though they are still not totally disengaged, which may make the 'creeping' part less noticeable while sitting still, but would eventually lead to increased clutch plate/pad wear.
 
The clutch is an "ON" mechanism. The only way to turn it "Off" is to pull the master in which pushed the slave piston which in turn pushes the push rods and pressure plate. This flattens out the spring (why you feel tension) and in turn creates a "gap" for the plates to spin freely. BUT, this gap fills with oil and the thicker the oil (or colder) the more "friction" it creates. This can cause the "jump/lurch" you can feel when putting it into gear for the first time from nuetral and why it is more noticeable when cold.

If the fluid is overfilled in the reservoir then it can actually cause the clutch to be actuated slightly as the fluid expands while it is warmed up from normal operation. This in turn can cause additional pressure on the release which causes additional heat and can lead to a quickly ramping heat/pressure gain. This is usually more of a problem on the brake side and can actually cause the brake to lock up.

The thicker oil causes the extra friction which can cause it to be harder to find nuetral.

Now, when you start talking about friction modifiers (or synthetic oil) then the clutch has to work harder to actually hold (after all it's trying to grab through something that's trying to cause less friction (which is what is needed to work)). This is the reason I don't like to use synthetic oil. For the average guy not running their bike hard they may very well be ok with the synthetic fluid. Makes for a nicer smoother shift but for guys like me the clutch simply won't hold.
 
I have been running full synthetic with the double D mod and a bunch of power and have never had the clutch slip. I have launched from 5 to 7k off the line and you can bet your ass when the lever is out the front wheel is floating or the rear is spinning. Just my input though, others might have had issues with stock clutches.
 
The DD will help overcome some of the issues with synthetic since it's doubling the clamping pressure. You will still have issues with grab but not as much.
 

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